Here are a few issues that students have run into:

• remember to remove the the line app.run(host='0.0.0.0', port=3001, debug=True) in the myapp.py file before deploying to Heroku; however, to run the web app from within the Udacity workspace, you do need that line of code
• In the web development lesson, the Flask application file was called worldbank.py. In the template code, the same file is called myapp.py. So the Procfile should contain the line web gunicorn myapp:app .
• The template files can be deployed to Heroku. In other words, the template files already contain a working, deployable web app. If you're having trouble deploying your app to Heroku, try deploying the template files first. That should help with debugging because then you will know if an issue relates to how you are interacting with Heroku, or if there's a bug in your code.